To reduce a system cost by reducing the number of signal lines needed to communicate a plurality of pieces of information and a plurality of information statuses.

A first function unit 1 and a second function unit 2 of each of function units composing an electronic device are connected through the signal line 3 for communicating a plurality of pieces of information and a plurality of information statuses. The first function unit 1 and second function unit 2 each have a data table of status patterns assigning statuses to the pieces of information. The first function unit 1 sends conversion data, which are subjected to conversion by referring to the data table, to the second function unit 2. The second function unit 2 reconverts the received conversion data to the status pattern by referring to the data table.